photo #8257963

This hooked form of the high, streaked ice-crystal cloud Cirrus is known as Cirrus uncinus (which is the Latin word for ‘hooked’). Sometimes called mares’ tails, these formations are traditionally associated with the arrival of unsettled weather. But this only applies when the clouds gather and invade the whole sky. Valerie Laabs-Siemon (Cloud Appreciation Society Member 62,461) spotted these patches of Cirrus uncinus over Clay Cliffs near Twizel, New Zealand. Hers heralded no change in the weather. They served instead just to highlight the jagged forms of the rock, which they did with a soft, silky flick of their tails.